Identification of regioisomers and enantiomers of triacylglycerols in different yeasts using reversed‐ and chiral‐phase LC – MS

LC with atmospheric pressure chemical ionization (ACPI) MS with RP and chiral phase was used for separation of triacylglycerols ( TAG s) from yeasts of the genera C andida , K luyveromyces , R hodotorula , S accharomyces , T orulospora , T richosporon , and Y arrowia . Chiral LC – APCI ‐ MS is based on using two columns in series packed with a 3,5‐dimethylphenyl carbamate modified β‐cyclodextrin chiral phase. All regioisomers and enantiomers of TAG s containing one to five double bonds were separated. Molecular species of TAG s, i.e. regioisomers and enantiomers, were identified and quantified by MS / MS . Among the 94 identified TAG s, the most abundant were triolein, oleopalmitoleoolein, and dipalmitoleoolein. In strains producing palmitoleic acid in amounts >25% of total fatty acids ( FA s), this acid, or unsaturated FA is bound in sn ‐1. In strains containing palmitoleic acid at 10–25% total FA s this acid is mainly bound in sn ‐3, saturated FA being bound in sn ‐1. Strains containing <10% palmitoleic acid form preferentially symmetrical TAG s.